title: Characterization of the Kingella kingae polysaccharide capsule and exopolysaccharide.
abstract: Recent evidence indicates that Kingella kingae produces a polysaccharide capsule. In an effort to determine the composition and structure of this polysaccharide capsule, in the current study we purified capsular material from the surface of K. kingae strain 269-492 variant KK01 using acidic conditions to release the capsule and a series of steps to remove DNA, RNA, and protein. Analysis of the resulting material by gas chromatography and mass spectrometry revealed N-acetyl galactosamine (GalNAc), 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo), and galactose (Gal). Further analysis by NMR demonstrated two distinct polysaccharides, one consisting of GalNAc and Kdo with the structure →3)-β-GalpNAc-(1→5)-β-Kdop-(2→ and the other containing galactose alone with the structure →5)-β-Galf-(1→. Disruption of the ctrA gene required for surface localization of the K. kingae polysaccharide capsule resulted in elimination of GalNAc and Kdo but had no effect on the presence of Gal in bacterial surface extracts. In contrast, deletion of the pamABCDE locus involved in production of a reported galactan exopolysaccharide eliminated Gal but had no effect on the presence of GalNAc and Kdo in surface extracts. Disruption of ctrA and deletion of pamABCDE resulted in a loss of all carbohydrates in surface extracts. These results establish that K. kingae strain KK01 produces a polysaccharide capsule with the structure →3)-β-GalpNAc-(1→5)-β-Kdop-(2→ and a separate exopolysaccharide with the structure →5)-β-Galf-(1→. The polysaccharide capsule and the exopolysaccharide require distinct genetic loci for surface localization.
authors.affiliation: Department of Pediatrics and Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America.
authors.forename: Kimberly F
authors.initials: KF
authors.lastname: Starr
authors.forename: Eric A
authors.initials: EA
authors.lastname: Porsch
authors.forename: Christian
authors.initials: C
authors.lastname: Heiss
authors.forename: Ian
authors.initials: I
authors.lastname: Black
authors.forename: Parastoo
authors.initials: P
authors.lastname: Azadi
authors.forename: Joseph W
authors.initials: JW
authors.lastname: St Geme
mesh_terms: D016667:Bacterial Capsules / Q000737:chemistry*; D017931:DNA Primers / Q000235:genetics; D005688:Galactosamine / Q000032:analysis; D005690:Galactose / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D017353:Gene Deletion; D005798:Genes, Bacterial / Q000235:genetics*; D017882:Kingella kingae / Q000737:chemistry* / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D013400:Sugar Acids / Q000032:analysis
chemical_list: D017931:DNA Primers; D011135:Polysaccharides, Bacterial; D013400:Sugar Acids; C002532:2-keto-3-deoxyoctonate; D005688:Galactosamine; D005690:Galactose